What does 650Cm mean in a Yamaha blaster?

The "650" in "Yamaha Blaster 650" refers to the displacement of the engine in cubic centimeters (cc). This means that the engine has a displacement of 650 cubic centimeters.

Engine displacement is the total volume of all the cylinders in an engine. It is calculated by multiplying the bore (the diameter of the cylinder) by the stroke (the distance the piston moves up and down) by the number of cylinders.

Displacement is an important factor in determining an engine's power and torque.